Ventilation devices for motor vehicles are known. They serve for bringing about an airflow in an interior of the motor vehicle and are of adjustable design. The adjustment firstly enables setting of the rate of the airflow and secondly the direction of flow of the airflow.
For adaptation of the airflow to meet requirements, the ventilation devices have ventilating ducts with perforated disks which are customarily installed in an interior component of a motor vehicle. The perforated disks are partially rotatable independently of one another about a longitudinal axis of the ventilating duct. The perforated disks are arranged axially along the longitudinal axis, and have openings through which the flow can pass. The openings can be completely or partially closed with the aid of the adjacent perforated disk.
Laid-open application DE 10 2015 206 621 A1 discloses a ventilating duct for a ventilation device which comprises a plurality of coaxially arranged perforated disks. The openings of the perforated disks are formed inclined in relation to a horizontal in such a manner that flow ducts in the manner of a spiral shape can be brought about.
Laid-open application DE 10 2013 213 277 A1 reveals a ventilating duct for a ventilation device which comprises a plurality of coaxially arranged perforated disks which are arranged rotatably relative to one another with the aid of an adjusting ring surrounding the perforated disks.
Laid-open application DE 10 2012 213 513 A1 discloses a ventilating duct for a ventilation device, comprising a plurality of coaxially arranged perforated disks which are rotatable relative to one another. The rotation takes place with the aid of an actuator which is arranged in the form of a disk and between the perforated disks, or is formed with a translationally movable drive element.
Laid-open specification DE 20 2011 000 453 U1 discloses a ventilating duct for a ventilation device which has two rotatably mounted perforated disks which are mounted coaxially with respect to each other and with respect to a fixed perforated disk. The two perforated disks are rotatable relative to the fixed perforated disk, wherein openings of the perforated disks and of the fixed perforated disk, through which openings the flow can pass, can be closed with the aid of the perforated disks.
Further ventilating ducts for ventilation devices comprising at least two perforated disks which are rotatable relative to one another can be gathered from the documents FR 2 792 256 B1, EP 1 332 900 B1, DE 10 2004 003 059 B4 and GB 1 436 838 A.